High shear process for the production of chloral

ABSTRACT

Use of a high shear mechanical device incorporated into a process for the production of chloral as a reactor device is capable of decreasing mass transfer limitations, thereby enhancing the chloral production process. A system for the production of chloral from acetaldehyde and chlorine, the system comprising a reactor and an external high shear device the outlet of which is fluidly connected to the inlet of the reactor; the high shear device capable of providing a dispersion of chlorine gas bubbles within a liquid, the bubbles having an average bubble diameter of less than about 100 μm.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 12/137,455 filed Jun. 11, 2008, which claims the benefit under35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 60/946,519filed Jun. 27, 2007, the disclosure of which is hereby incorporatedherein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

BACKGROUND OF THE INVENTION

1. Technical Field

The present disclosure relates generally to the production of chloral bychlorination of acetaldehyde, and more particularly to apparatus andmethods for converting acetaldehyde to chloral, via liquid phasechlorination, in a high shear process. More specifically, the disclosurerelates to the reduction of mass transfer limitations in apparatus andmethods for converting acetaldehyde to chloral.

2. Background of the Invention

Chloral, CCl₃CH═O, also known as trichloroacetaldehyde ortrichloroethanal is an organic halide discovered in 1832 by Justus vonLiebig. Chloral in pure form is a colorless oily liquid soluble inalcohol and ether. Chloral reacts with water to form chloral hydratewhich has medicinal properties as a potent sedative. Historically,chloral was reacted with chlorobenzene in the presence of sulfuric acidcatalyst to form DDT in the pesticide industry.

Chloral is typically produced by the chlorination of ethanol oraldehyde. Specifically during the chlorination of aldehydes, the rawmaterials acetaldehyde or paraldehyde may be used. Due to loss ofethanol via formation of ethyl chloride and ethyl acid sulfate as wellas environmental and waste disposal problems associated with productionof these materials, the ethanol process has been largely replaced byaldehyde chlorination. Acetaldehyde chlorination is carried out via thereaction:CH₃CHO+3Cl₂→CCl₃CHO+3HCl  (1)Chloral is an unstable compound, making it highly reactive such that itmay combine with many chemical substances, including itself, ordecompose.

Conventionally, the commercial practice of manufacturing chloral fromacetaldehyde involves adding water to the material undergoingchlorination to inhibit decomposition of dichloroacetaldehyde andchloral by their reactions with chlorine. Chloroform and carbontetrachloride result from decomposition. Presumably the decompositionreactions are inhibited by formation of the hydrates.

The hydrates are much more stable and therefore production of crudechloral containing only trace amounts of dichloroacetaldehyde, withoutsignificant chloroform and carbon tetrachloride co-production, can beaccomplished. The chlorination reaction in addition generatessignificant amounts of byproduct hydrogen chloride gas (HCl) some ofwhich tends to be absorbed by the wet crude chloral. To produce thepurified chloral from the wet crude product, water and HCl must beremoved. Many patents discuss methods of wet crude chloral purification,including U.S. Pat. Nos. 4,513,152; 774,151; 2,443,183; 2,478,152;2,478,741; 2,768,173; 955,589; and 661,092.

Accordingly, there is a need in the industry for improved methods ofproducing chloral from acetaldehyde and chlorine whereby productionrates are increased, unwanted reactions are reduced, and milder reactionconditions, such as lower temperature and pressure, are commerciallyfeasible.

SUMMARY OF THE INVENTION

A high shear system and process for accelerating chloral production isdisclosed. The high shear process reduces mass transfer limitations,thereby enhancing the effective reaction rate and enabling a reductionin reactor temperature, a reduction in reactor pressure, a reduction incontact time, and/or an increase in product yield. In accordance withcertain embodiments of the present disclosure, a process is providedthat makes possible an increase in the rate of a liquid phase processfor the production of chloral from acetaldehyde by providing for moreoptimal time, temperature, and pressure conditions than areconventionally used.

In an embodiment described in the present disclosure, a process employsa high shear mechanical reactor to provide enhanced time, temperature,and pressure reaction conditions resulting in accelerated chemicalreactions between multiphase reactants. Further, a process disclosed inan embodiment described herein comprises the use of a pressurized highshear device to provide for the production of chloral without the needfor high volume, high pressure reactors, or excess chlorine.

These and other embodiments, features, and advantages will be apparentin the following detailed description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more detailed description of a preferred embodiment described inthe present disclosure, reference will now be made to the accompanyingdrawings, wherein:

FIG. 1 is a cross-sectional diagram of a high shear device for theproduction of chloral.

FIG. 2 is a process flow diagram according to an embodiment of thepresent disclosure for a mediator-assisted high shear process forproduction of chloral.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Overview

An improved process and system for the production of chloral viachlorination of acetaldehyde employs an external or inline high shearmechanical device. The high shear device is a mechanical reactor, mixer,or mill to provide rapid contact and mixing of chemical ingredients inthe device. Chloral production results from the chlorination ofacetaldehyde or paraldehyde. These raw materials are collectively termedaldehydes hereinafter.

Chemical reactions involving liquids, gases, and solids rely on the lawsof kinetics that involve time, temperature, and pressure to define therate of reactions. In cases where it is desirable to react two or moreraw materials of different phases (e.g. solid and liquid; liquid andgas; solid, liquid, and gas), one of the limiting factors in controllingthe rate of reaction involves the contact time of the reactants. In thecase of heterogeneously catalyzed reactions there is the additional ratelimiting factor of having the reacted products removed from the surfaceof the catalyst to enable the catalyst to catalyze further reactants.

In conventional reactors, contact time for the reactants and/or catalystis often controlled by mixing which provides contact with two or morereactants involved in a chemical reaction. A reactor assembly thatcomprises a high shear device makes possible decreased mass transferlimitations and thereby allows the reaction to more closely approachkinetic limitations. When reaction rates are accelerated, residencetimes may be decreased, thereby increasing obtainable throughput.Alternatively, where the current yield is acceptable, decreasing therequired residence time allows for the use of lower temperatures and/orpressures than conventional processes.

High Shear Device

High shear devices (HSD) such as a high shear mixer, or high shear mill,are generally divided into classes based upon their ability to mixfluids. Mixing is the process of reducing the size of inhomogeneousspecies or particles within the fluid. One metric for the degree orthoroughness of mixing is the energy density per unit volume that themixing device generates to disrupt the fluid particles. The classes aredistinguished based on delivered energy density. There are three classesof industrial mixers having sufficient energy density to consistentlyproduce mixtures or emulsions with particle or bubble sizes in the rangeof 0 to 50 μm

Homogenization valve systems are typically classified as high energydevices. Fluid to be processed is pumped under very high pressurethrough a narrow-gap valve into a lower pressure environment. Thepressure gradients across the valve and the resulting turbulence andcavitations act to break-up any particles in the fluid. These valvesystems are most commonly used in milk homogenization and can yieldaverage particle size range from about 0.01 μm to about 1 μm. At theother end of the spectrum are high shear device systems classified aslow energy devices. These systems usually have paddles or fluid rotorsthat turn at high speed in a reservoir of fluid to be processed, whichin many of the more common applications is a food product. These systemsare usually used when average particle, or bubble, sizes of greater than20 microns are acceptable in the processed fluid.

Between low energy-high shear mixers and homogenization valve systems,in terms of the mixing energy density delivered to the fluid, arecolloid mills, which are classified as intermediate energy devices. Thetypical colloid mill configuration includes a conical or disk rotor thatis separated from a complementary, liquid-cooled stator by aclosely-controlled rotor-stator gap, which is maybe between 0.025 mm and10.0 mm. Rotors are usually driven by an electric motor through a directdrive or belt mechanism. Many colloid mills, with proper adjustment, canachieve average particle, or bubble, sizes of about 0.01 μm to about 25μm in the processed fluid. These capabilities render colloid millsappropriate for a variety of applications including colloid andoil/water-based emulsion processing such as that required for cosmetics,mayonnaise, silicone/silver amalgam formation, or roofing-tar mixing.

An approximation of energy input into the fluid (kW/L/min) can be madeby measuring the motor energy (kW) and fluid output (L/min). Inembodiments, the energy expenditure of a high shear device is greaterthan 1000 W/m³. In embodiments, the energy expenditure is in the rangeof from about 3000 W/m³ to about 7500 W/m³. The shear rate generated ina high shear device may be greater than 20,000 s⁻¹. In embodiments, theshear rate generated is in the range of from 20,000 s⁻¹ to 100,000 s⁻¹.

Tip speed is the velocity (m/sec) associated with the end of one or morerevolving elements that is transmitting energy to the reactants. Tipspeed, for a rotating element, is the circumferential distance traveledby the tip of the rotor per unit of time, and is generally defined bythe equation V(m/sec)=π·D·n, where V is the tip speed, D is the diameterof the rotor, in meters, and n is the rotational speed of the rotor, inrevolutions per second. Tip speed is thus a function of the rotordiameter and the rotation rate. Also, tip speed may be calculated bymultiplying the circumferential distance transcribed by the rotor tip,2πR, where R is the radius of the rotor (meters, for example) times thefrequency of revolution (for example revolutions per minute, rpm).

For colloid mills, typical tip speeds are in excess of 23 m/sec (4500ft/min) and can exceed 40 m/sec (7900 ft/min). For the purpose of thepresent disclosure the term ‘high shear’ refers to mechanicalrotor-stator devices, such as mills or mixers, that are capable of tipspeeds in excess of 5 m/sec (1000 ft/min) and require an external,mechanically-driven power device to drive energy into the stream ofproducts to be reacted. A high shear device combines high tip speedswith a very small shear gap to produce significant friction on thematerial being processed. Accordingly, a local pressure in the range ofabout 1000 MPa (about 145,000 psi) to about 1050 MPa (152,300 psi), andelevated temperatures at the tip of the shear device are produced duringoperation. In certain embodiments, the local pressure is at least 1034MPa. In further embodiments, the pressure is dependent on the viscosityof the solution, rotor tip speed, and shear gap.

Referring now to FIG. 1, there is presented a schematic diagram of ahigh shear device 200. High shear device 200 comprises at least onerotor-stator combination. The rotor-stator combinations may also beknown as generators 220, 230, 240 or stages without limitation. The highshear device 200 comprises at least two generators, and most preferably,the high shear device comprises at least three generators.

The first generator 220 comprises rotor 222 and stator 227. The secondgenerator 230 comprises rotor 223, and stator 228; the third generatorcomprises rotor 224 and stator 229. For each generator 220, 230, 240 therotor is rotatably driven by input 250. The generators 220, 230, 240rotate about axis 260 in rotational direction 265. Stator 227 is fixablycoupled to the high shear device wall 255.

The generators include gaps between the rotor and the stator. The firstgenerator 220 comprises a first gap 225; the second generator 230comprises a second gap 235; and the third generator 240 comprises athird gap 245. The gaps 225, 235, 245 are between about 0.025 mm (0.01in) and 10.0 mm (0.4 in) wide. Alternatively, the process comprisesutilization of a high shear device 200 wherein the gaps 225, 235, 245are between about 0.5 mm (0.02 in) and about 2.5 mm (0.1 in). In certaininstances the gap is maintained at about 1.5 mm (0.06 in).Alternatively, the gaps 225, 235, 245 are different between generators220, 230, 240. In certain instances, the gap 225 for the first generator220 is greater than about the gap 235 for the second generator 230,which is greater than about the gap 245 for the third generator 240.

Additionally, the width of the gaps 225, 235, 245 may comprise a coarse,medium, fine, and super-fine characterization. Rotors 222, 223, and 224and stators 227, 228, and 229 may be toothed designs. Each generator maycomprise two or more sets of rotor-stator teeth, as known in the art.Rotors 222, 223, and 224 may comprise a number of rotor teethcircumferentially spaced about the circumference of each rotor. Stators227, 228, and 229 may comprise a number of stator teethcircumferentially spaced about the circumference of each stator. Inembodiments, the inner diameter of the rotor is about 11.8 cm. Inembodiments, the outer diameter of the stator is about 15.4 cm. Infurther embodiments, the rotor and stator may have an outer diameter ofabout 60 mm for the rotor, and about 64 mm for the stator.Alternatively, the rotor and stator may have alternate diameters inorder to alter the tip speed and shear pressures. In certainembodiments, each of three stages is operated with a super-finegenerator, comprising a gap of between about 0.025 mm and about 3 mm.When a feed stream 205 including solid particles is to be sent throughhigh shear device 200, the appropriate gap width is first selected foran appropriate reduction in particle size and increase in particlesurface area. In embodiments, this is beneficial for increasing catalystsurface area by shearing and dispersing the particles.

High shear device 200 is fed a reaction mixture comprising the feedstream 205. Feed stream 205 comprises an emulsion of the dispersiblephase and the continuous phase. Emulsion refers to a liquefied mixturethat contains two distinguishable substances (or phases) that will notreadily mix and dissolve together. Most emulsions have a continuousphase (or matrix), which holds therein discontinuous droplets, bubbles,and/or particles of the other phase or substance. Emulsions may behighly viscous, such as slurries or pastes, or may be foams, with tinygas bubbles suspended in a liquid. As used herein, the term “emulsion”encompasses continuous phases comprising gas bubbles, continuous phasescomprising particles (e.g., solid catalyst), continuous phasescomprising droplets of a fluid that is substantially insoluble in thecontinuous phase, and combinations thereof.

Feed stream 205 may include a particulate solid catalyst component. Feedstream 205 is pumped through the generators 220, 230, 240, such thatproduct dispersion 210 is formed. In each generator, the rotors 222,223, 224 rotate at high speed relative to the fixed stators 227, 228,229. The rotation of the rotors pumps fluid, such as the feed stream205, between the outer surface of the rotor 222 and the inner surface ofthe stator 227 creating a localized high shear condition. The gaps 225,235, 245 generate high shear forces that process the feed stream 205.The high shear forces between the rotor and stator functions to processthe feed stream 205 to create the product dispersion 210. Each generator220, 230, 240 of the high shear device 200 has interchangeablerotor-stator combinations for producing a narrow distribution of thedesired bubble size, if feedstream 205 comprises a gas, or globule size,if feedstream 205 comprises a liquid, in the product dispersion 210.

The product dispersion 210 of gas particles, or bubbles, in a liquidcomprises an emulsion. In embodiments, the product dispersion 210 maycomprise a dispersion of a previously immiscible or insoluble gas,liquid, or solid into the continuous phase. The product dispersion 210has an average gas particle, or bubble, size less than about 1.5 μm;preferably the bubbles are sub-micron in diameter. In certain instances,the average bubble size is in the range from about 1.0 μm to about 0.1μm. Alternatively, the average bubble size is less than about 400 nm(0.4 μm) and most preferably less than about 100 nm (0.1 μm). The highshear device 200 produces a gas emulsion capable of remaining dispersedat atmospheric pressure for at least about 15 minutes. For the purposeof this disclosure, an emulsion of gas particles, or bubbles, in thedispersed phase in product dispersion 210 that are less than 1.5 μm indiameter may comprise a micro-foam.

Not to be limited by a specific theory, it is known in emulsionchemistry that sub-micron particles, or bubbles, dispersed in a liquidundergo movement primarily through Brownian motion effects. The bubblesin the emulsion of product dispersion 210 created by the high sheardevice 200 may have greater mobility through boundary layers of solidcatalyst particles, thereby facilitating and accelerating the catalyticreaction through enhanced transport of reactants.

The rotor is set to rotate at a speed commensurate with the diameter ofthe rotor and the desired tip speed as described above. Transportresistance is reduced by incorporation of high shear device 200 suchthat the velocity of the reaction is increased by at least about 5%.Alternatively, the high shear device 200 comprises a high shear colloidmill that serves as an accelerated rate reactor (ARR). The acceleratedrate reactor comprises a single stage dispersing chamber. Theaccelerated rate reactor comprises a multiple stage inline dispersercomprising at least 2 stages.

Selection of the high shear device 200 is dependent on throughputrequirements and desired particle or bubble size in the outletdispersion 210. In certain instances, high shear device 200 comprises aDispax Reactor® of IKA® Works, Inc. Wilmington, N.C. and APV NorthAmerica, Inc. Wilmington, Mass. Model DR 2000/4, for example, comprisesa belt drive, 4M generator, PTFE sealing ring, inlet flange 1″ sanitaryclamp, outlet flange ¾″ sanitary clamp, 2HP power, output speed of 7900rpm, flow capacity (water) approximately 300-700 l/h (depending ongenerator), a tip speed of from 9.4-41 m/s (about 1850 ft/min to about8070 ft/min). Several alternative models are available having variousinlet/outlet connections, horsepower, nominal tip speeds, output rpm,and nominal flow rate.

Without wishing to be limited to a particular theory, it is believedthat the level or degree of high shear mixing is sufficient to increaserates of mass transfer and may also produce localized non-idealconditions that enable reactions to occur that would not otherwise beexpected to occur based on Gibbs free energy predictions. Localized nonideal conditions are believed to occur within the high shear deviceresulting in increased temperatures and pressures with the mostsignificant increase believed to be in localized pressures. The increasein pressures and temperatures within the high shear device areinstantaneous and localized and quickly revert back to bulk or averagesystem conditions once exiting the high shear device. In some cases, thehigh shear mixing device induces cavitation of sufficient intensity todissociate one or more of the reactants into free radicals, which mayintensify a chemical reaction or allow a reaction to take place at lessstringent conditions than might otherwise be required. Cavitation mayalso increase rates of transport processes by producing local turbulenceand liquid micro-circulation (acoustic streaming). An overview of theapplication of cavitation phenomenon in chemical/physical processingapplications is provided by Gogate et al., “Cavitation: A technology onthe horizon,” Current Science 91 (No. 1): 35-46 (2006). The high shearmixing device of certain embodiments of the present system and methodsis operated under what is believed to be cavitation conditions effectiveto dissociate the acetaldehyde into free radicals exposed to chlorinegas for the formation of chloral product.

Description of High Shear Chloral Production Process and System

The high shear chloral production process and system of the presentdisclosure will now be described in relation to FIG. 2. FIG. 2 is arepresentative process flow diagram of a high shear system (HSS) 100 forthe production of chloral from acetaldehyde and chlorine gas. FIG. 2illustrates the basic components of a representative high shear chloralproduction system in which the process is carried out. These componentscomprise pump 5, high shear device (HSD) 40, and reactor 10. The highshear chloral production process and system create a chlorine (or othergaseous reactant) emulsion in the feed stream including aldehyde priorto introduction to the reactor 10.

Pump 5 is used to provide a controlled flow throughout high shear device40 and HSS 100. In this way, HSS 100 uses high shear to enhance reactantintimate mixing. In embodiments, pump 5 increases the pressure of thereactant stream 21 to greater than about 203 kPa (2 atm). Alternatively,the pump 5 may pressurize reactant stream 21 to a pressure of greaterthan about 2030 kPa (20 atm). The increased pressure of reactant stream21 can be used to accelerate reactions. The limiting factor for pressurein HSS 100 may be the pressure limitations of pump 5 and high sheardevice 40. Preferably, all contact parts of pump 5 comprise stainlesssteel. Pump 5 may be any suitable pump, for example, a Roper Type 1 gearpump, Roper Pump Company (Commerce Ga.) or a Dayton Pressure BoosterPump Model 2P372E, Dayton Electric Co. (Niles, Ill.).

Pump 5 pressurizes reactant stream 21. Reactant stream 21 comprisesliquid aldehydes such as, but not limited to, acetaldehyde, paraldehyde(trimer of acetaldehyde), and similar compounds as are known to one ofskill in the art. Reactant stream 21 may further comprise water.Likewise, acetaldehyde in different forms can be used. The prior artdisclosed in U.S. Pat. Nos. 2,702,303 and 2,768,173 describes the use ofacetaldehyde and its reversible polymers (e.g. paraldehyde, (CH₃CHO)₃),the former disclosing a completely aqueous process which is the usualcommercial practice, and the latter disclosing a process of anhydrouschlorination of paraldehyde to the hexachloroparaldehyde state, followedby aqueous chlorination to crude chloral. The high shear system andprocess may be used for either method; the aqueous process withacetaldehyde as liquid solution will be described in detail.

The pump exit stream 12 comprises a pressurized stream analogous to thereactant stream 21. Pump exit stream 12 is in fluid communication withhigh shear device (HSD) inlet stream 13. In certain embodiments pumpexit stream 12 and HSD inlet stream 13 are a continuous stream. Pumpexit stream 12 may be mixed with dispersible gas stream 22 comprisingchlorine gas. The dispersible gas stream 22 may be continuously fed intopump exit stream 12 to form HSD inlet stream 13. Dispersible gas stream22 may be injected into HSD inlet stream 13.

Dispersible gas stream 22 and pressurized pump exit stream 12 areinjected into HSD inlet stream 13 for processing by high shear device40. HSD inlet stream 13 is in fluid communication with HSD 40. Asdiscussed in detail above, high shear device 40 is a mechanical devicethat utilizes, for example, a stator rotor mixing head with a fixed gapbetween the stator and rotor. Dispersible gas stream 22 comprisingchlorine is dispersed in pump exit stream 12 comprising aldehydes forthe production of chloral. In high shear device 40, chlorine gas andliquid stream 12 are mixed to form an emulsion comprising microbubblesand nanobubbles of chlorine gas. In embodiments, the resultantdispersion comprises bubbles in the submicron size. In embodiments, theresultant dispersion has an average bubble size less than about 1.5 μm.In embodiments, the mean bubble size is less than from about 0.1 μm toabout 1.5 μm. Not to be limited by a specific method, it is known inemulsion chemistry that submicron particles dispersed in a liquidundergo movement primarily through Brownian motion effects. Thus it isbelieved that submicron gas particles created by the high shear device40 have greater mobility through boundary layers of solid catalystparticles thereby facilitating and accelerating the catalytic reactionthrough greater transport of reactants. In embodiments, the high shearmixing produces gas bubbles capable of remaining dispersed atatmospheric pressure for about 15 minutes or longer depending on thebubble size. In embodiments, the mean bubble size is less than about 400nm; more preferably, less than about 100 nm. HSD 40 serves to create anemulsion of chlorine bubbles within high shear inlet stream 13comprising aqueous aldehydes and chlorine gas. The emulsion may furthercomprise a micro-foam. In embodiments there may be several high sheardevices 40 used in series.

The HSD exit stream 18 comprises the emulsion. HSD 18 is in fluidcommunication with reactor 10. In certain embodiments, HSD 18 undergoesfurther processing to form reactor inlet stream 19. Reactor inlet stream19 enters reactor 10 for chloral production. Chlorination reactions willoccur whenever suitable time, temperature, and pressure conditionsexist. In this sense, chlorination could occur at any point in HSS 100where temperature and pressure conditions are suitable. In suchembodiments, a discrete reactor is often desirable to allow forincreased residence time, agitation, and heating/cooling. Reactor 10 maybe any reactor in which multiphase chlorination may propagate, as willbe known by one skilled in the art. In embodiments, chloral productionis continuous.

In embodiments, reactor 10 is a continuous stirred tank reactor. Thereaction may be maintained at the specified reaction temperature, usingcooling coils in the reactor 10 to maintain reaction temperature, as isknown to those of skill in the art. The use of external heating and/orcooling heat exchange devices may regulate the reaction temperature.Suitable locations for external heat exchangers would be between thereactor 10 and the pump 5; between the pump 5 and the high shear mixer40; and/or between the high shear device 40 and the reactor 10. Thereare many types of heat transfer devices that may be suitable and areknown to those experienced in the art. Such exchangers includeshell-and-tube, plate, and coil heat exchangers. Reactor 10 may furthercomprise a stirring system and level regulator as known to those ofskill in the art. In certain embodiments, the reactor is maintained at atemperature of below about 40° C.

Reaction products are removed from the reactor by product stream 16.Product stream 16 may comprise chloral, water, dissolved HCl, and suchcommonly found contaminants as monochloroacetaldehyde,dichloroacetaldehyde, butyl chloral, the chloroacetic acids, carbontetrachloride, and chloroform. Other contaminants may be present,depending on the conditions in the reactor, and the reactants for thechlorination that are utilized. Variations of ethanol or aldehydeprocesses for chloral production, known to one skilled in the art, willproduce crude chloral amenable to purification

Product stream 16 comprising chloral may be purified by any means knownto those of skill in the art. For example, U.S. Pat. No. 4,513,152describes introducing crude chloral to mixing vessel 30. Mixing vessel30 is in fluid communication with sulfuric acid stream 37 obtained froma sulfuric acid source 38. Mixing vessel 30 is in fluid communicationwith sulfuric acid stream 37 by supply stream 39. In certainembodiments, supply stream 39 comprises processing the sulfuric acid. Incertain embodiments, mixing vessel 30 comprises agitation and heating toremove hydrochloric acid. Hydrochloric acid byproduct may be removed byacid exit stream 17. In further embodiments, exit stream 17 may comprisea reflux condenser. Waste sulfuric acid stream 26 exits the process.Mixing vessel 30 produces a liquid chloral product stream 14.

Chloral product stream 14 may be further treated in purifying reactor50. Purifying reactor 50 comprises further treatment with sulfuric acidfrom sulfuric acid inlet 36, to further remove hydrochloric acidactivity. The acids are removed from purifying reactor 50 by outlet 31,or by sulfuric acid recycle stream 8. Sulfuric acid stream 8 may berecycled to mixing vessel 30. The purified chloral exits purifyingreactor 50 via chloral stream 35. In certain embodiments, chloral stream35 further comprises distillation. Chloral stream 35 may furthercomprise any process for refining chloral for additional chemical uses.

In embodiments there may be several high shear devices 40 used inseries. Two or more high shear devices 40 such as high shear colloiddevices are aligned in series, and are used to further enhance thereaction. Operation of multiple high shear devices 40 may be in eitherbatch or continuous mode. In some instances in which a single pass or“once through” process is desired, the use of multiple high sheardevices 40 in series may also be advantageous. Multiple high sheardevices operated in series may permit the removal of reactor 10 from thehigh shear system 100. In some embodiments, multiple high shear devices40 are operated in parallel, and the outlet dispersions therefrom areintroduced into one or more reactor(s) 10.

The application of enhanced mixing of the reactants by high shear device40 results in greater conversion of acetaldehyde to chloral in someembodiments of the process. Further, the enhanced mixing of the chlorinein the aqueous aldehyde solution provides an increase in throughput ofthe process stream of the high shear system 100. In certain instances,the high shear device 40 is incorporated into an established process,thereby enabling an increase in production (i.e., greater throughput).In contrast to some existing methods that attempt to increase the degreeof conversion of ethylene by increasing reactor pressures, the superiordissolution and/or emulsification provided by high shear mixing allowsin many cases a decrease in overall operating pressure while maintainingor even increasing reaction rate.

While preferred embodiments of the invention have been shown anddescribed, modifications thereof can be made by one skilled in the artwithout departing from the spirit and teachings of the invention. Theembodiments described herein are exemplary only, and are not intended tobe limiting. Many variations and modifications of the inventiondisclosed herein are possible and are within the scope of the invention.Where numerical ranges or limitations are expressly stated, such expressranges or limitations should be understood to include iterative rangesor limitations of like magnitude falling within the expressly statedranges or limitations (e.g., from about 1 to about 10 includes, 2, 3, 4,etc.; greater than 0.10 includes 0.11, 0.12, 0.13, and so forth). Use ofthe term “optionally” with respect to any element of a claim is intendedto mean that the subject element is required, or alternatively, is notrequired. Both alternatives are intended to be within the scope of theclaim. Use of broader terms such as comprises, includes, having, etc.should be understood to provide support for narrower terms such asconsisting of, consisting essentially of, comprised substantially of,and the like.

Accordingly, the scope of protection is not limited by the descriptionset out above but is only limited by the claims which follow, that scopeincluding all equivalents of the subject matter of the claims. Each andevery claim is incorporated into the specification as an embodiment ofthe present invention. Thus, the claims are a further description andare an addition to the preferred embodiments of the present invention.The discussion of a reference in the Description of Related Art is notan admission that it is prior art to the present invention, especiallyany reference that may have a publication date after the priority dateof this application. The disclosures of all patents, patentapplications, and publications cited herein are hereby incorporated byreference, to the extent they provide exemplary, procedural or otherdetails supplementary to those set forth herein.

1. A system for the production of chloral, the system comprising: avessel containing an aqueous reactant solution, comprising aldehyde; apump for pressurizing the vessel; a high shear device having an inletfluidly connected to the vessel, wherein the high shear device comprisesat least one rotor and at least one stator having a minimum clearancetherebetween and configured to produce a dispersion of chlorine gas inthe aqueous reactant solution comprising aldehyde, the dispersion havingan average bubble diameter of less than about 5 μm; and a reactorfluidly connected to the high shear device, wherein the reactor is adiscrete vessel configured to maintain the dispersion at a temperatureof less than about 40° C. to form products having a chloral portion. 2.The system of claim 1 wherein the high shear device comprises at leasttwo rotors and at least two stators.
 3. The system of claim 1 whereinthe high shear device is adapted to rotate the at least one rotor at atip speed of at least 5 m/sec.
 4. The system of claim 1 wherein the highshear device is adapted to rotate the at least one rotor at a tip speedof at least 20 m/sec.
 5. The system of claim 1 wherein the high sheardevice is configured to produce a localized pressure of at least about1000 MPa at the tip of the rotor during operation of the high sheardevice.
 6. The system of claim 1 wherein the high shear device isconfigured to produce a shear rate of greater than about 20,000 s⁻¹. 7.The system of claim 1 wherein the minimum clearance between the at leastone rotor and the at least on stator is in the range of from 0.5 mm toabout 2.5 mm.
 8. The system of claim 1, wherein the pump is configuredto pressurize the aqueous solution to at least about 203 kPa.
 9. Thesystem of claim 1, wherein the aqueous solution comprises liquidaldehydes.
 10. The system of claim 1, wherein the reactor comprises anoutlet, the outlet fluidly connected to the vessel, and configured torecycle a portion of the dispersion to the high shear device.
 11. Thesystem of claim 1, further comprising: a second vessel fluidly connectedto the reactor, wherein the second vessel is configured to stabilize theproducts having a chloral portion with an acid portion; and a separatorfluidly connected to the vessel, wherein the separator is configured toseparate the acid portion from the chloral portion, and recycle the acidportion to the second vessel.
 12. The system of claim 11, wherein theseparator is configured to produce chloral.